In recent years, silicon carbide (SiC) has been increasingly employed as a material for forming a semiconductor device such as a transistor and a diode in order to allow an increase in the breakdown voltage and a decrease in loss, and also allow use in a high temperature environment, and the like. Silicon carbide serves as a wide band gap semiconductor having a band gap greater than that of silicon (Si) which has been conventionally widely used as a material forming a semiconductor device. Accordingly, when silicon carbide is employed as a material for forming a semiconductor device, an increase in the breakdown voltage, a decrease in the on-resistance and the like in the semiconductor device can be achieved. Furthermore, the semiconductor device formed using silicon carbide as a material also has an advantage that the deterioration of the characteristics obtained when used in a high temperature environment is relatively small as compared to a semiconductor device formed using silicon as a material.
Several semiconductor devices have been proposed in a variety of structures, to which SiC having the above-described excellent characteristics can be applied as a material (for example, see Japanese Patent Laying-Open No. 2003-068762 (Patent Document 1)). Furthermore, in the process of manufacturing a semiconductor device formed using SiC as a material, impurities are often introduced into a wafer made of SiC by ion implantation. Thus, various methods for satisfactorily performing ion implantation have also been proposed (for example, see Japanese Patent Laying-Open No. 2006-332180 (Patent Document 2) and Japanese Patent Laying-Open No. 2008-147576 (Patent Document 3)).